Short of suing me for it (after finding out who I am and making sure I own the games), how would they do that for non-DRM games whose installer lives on my hard drive and that I can install whenever I want, wherever I want?

Is the “everything is a rental and you use it on sufferance until we say so” bullshit so ingrained now that people are no longer able to conceive of other ways for things to work?

More than one group of custodians, ideally with conflicting interests, watching one another? Essentially some system of checks and balances?

IMO, this seems exactly what the fediverse needs to thrive. The whole “choose a server” thing is a big disincentive to adoption by most people.